Abstract: The present invention relates to an apparatus (10) apparatus for the detection of carbon dioxide. It is described to place (210) a part of a housing in contact with a skin area of a patient. the part of the housing and a gas measuring chamber within the housing are configured such that gases diffusing through the skin area of the patient enter the gas measuring chamber. radiation is emitted (220) from a radiation source within the housing, wherein at least some of the radiation emitted by the radiation source enters the gas measuring chamber. The radiation entering the gas measuring chamber has wavelengths that extend over an absorption band of carbon dioxide and has wavelengths that extend over a region other than the absorption band of carbon dioxide. A radiation filter is positioned (230) relative to the gas measuring chamber such that an interaction radiation path is defined between the radiation source through the gas measuring chamber to the radiation filter.

Abstract: It is commonly known within the art of cutaneous/transcutaneous blood gas monitoring to warm up the skin of the patient to allow carbon dioxide and oxygen to diffuse easily through the skin. This is especially the case for transcutaneous partial pressure monitoring of oxygen. Heating the skin to 43° C. to 45° C. over several hours or days may cause damage to the skin. In order to avoid or minimize the risk of these damage, it is proposed to monitor the blood gases at a lower temperature with a cutaneous sensor, and intermittently warm up the skin to a temperature of 42° C. or more for a short duration to monitor the transcutaneous partial pressure of oxygen, before lowering the temperature to the lower set point.

Abstract: Herein is disclosed a sensor for noninvasive measurement of the partial pressure of CO2 (pCO2) in the skin of a human. The sensor comprises a housing, a gas measuring chamber for measuring gases, at least one chimney for communication of gases diffusing through the skin to the gas measuring chamber, a broad band light source transmitting light into the gas measuring chamber and a detector system comprising a first and a second photodetector. The first photodetector detects light at a wavelength wherein CO2 absorbs light and the second photodetector acts as a zero reference detector by measuring light in a freeband where no gases absorb light.

Abstract: A sensor and an apparatus for non-invasive measurement of an analyte concentration, the apparatus comprising: a first thermal sensor operable to determine a temperature indicative of a temperature at a location on a skin of a subject, an analyte sensor operable to generate a measurement indicative of a concentration of the analyte, a heater; a controller operable to receive a temperature signal from at least the first thermal sensor and to adjust the heater to maintain a thermal equilibrium at said location on the skin; and a processor configured to convert the measurement to a calculated analyte concentration value at a predetermined temperature.

Abstract: The proposed invention provides a method of monitoring the dry cleaning progress of a transcutaneous sensor having an electrode for measuring pCO2 and an electrode for measuring pO2, both electrodes opening into a measuring surface of the sensor. The method comprises receiving an AC signal from the pCO2 electrode, initiating a cleaning of the sensor, and monitoring the cleaning progress by analyzing AC signals subsequently received from the pCO2 electrode.

Abstract: The proposed invention provides a method of monitoring the dry cleaning progress of a transcutaneous sensor having an electrode for measuring pCO2 and an electrode for measuring pO2, both electrodes opening into a measuring surface of the sensor. The method comprises receiving an AC signal from the pCO2 electrode, initiating a cleaning of the sensor, and monitoring the cleaning progress by analyzing AC signals subsequently received from the pCO2 electrode.

Abstract: In a process for measuring partial transcutaneous CO2 pressure on an earlobe by means of a sensor having a measuring device for measuring the partial transcutaneous CO2 pressure and a heating system for heating a sensor contact surface for contact with the earlobe, the sensor contact surface is heated. During a first phase, the sensor contact surface is kept at an elevated temperature of at least 41.5° C. in order to prevent the measured value of partial transcutaneous CO2 pressure from exceeding, due to the measurement process itself, the partial transcutaneous CO2 pressure achieved after stabilization. The temperature of the sensor contact surface is then reduced to between 37° C. and 41° C. This facilitates considerably faster evaluation of the measured values.